Medical instrument retainer assembly and method of making the retainer

ABSTRACT

A retainer assembly for retaining a medical device in a container having a perforated wall includes a retainer with a rigid support portion having at least one leg and a flexible, resilient instrument holding portion intimately bonded to the support portion so that the retainer is devoid of cracks and crevices between said portions. Each leg has a free end and an axial passage extending into the leg from that end so that the retainer may be positioned on the container wall with each opening in register with a perforation therein. A fastener extends into the passage of each leg and the underlying perforation from below the wall to anchor each leg to the wall under pressure thereby providing a seal between each leg and the wall. Various retainer embodiments and a method for making same are also disclosed.

BACKGROUND OF THE INVENTION

This invention relates to a retainer assembly for retaining medicalinstruments. It relates especially to a retainer assembly capable ofholding medical instruments at fixed positions in a tray or othercontainer while maintaining sterile conditions within the container.

There exists in the prior art various retainers and accessories forfixing the positions of articles of one kind or another. These includehooks, pegs, clips, brackets, etc. Such retainers may be used in a widevariety of applications. For example, they are commonly used in themedical field to fix the positions of various surgical instruments,devices and prostheses while those articles are being transported,sterilized and processed in one way or another. Accordingly, we willdescribe the invention in that context. It should be understood,however, that the present invention has application in other fields isbesides the medical field.

Medical instruments are often transported in trays. Prior to use, suchinstruments are placed in the tray and subjected to sterilization. Toimprove the circulation of steam throughout the tray, the tray bottomwall and perhaps also the side wall are usually perforated. In order tomaintain a separation between the various instruments in the tray, theinstruments are supported or retained by posts, brackets or otherretainers anchored to the tray. Following sterilization, the tray fullof instruments may be transported to an operating room and placed closeto a surgical team whose members may withdraw the instruments from thetray as needed for the particular surgical procedure being performed.Usually, the instruments are selectively arranged or organized in thetray so that they can be picked from the tray in the order in which theyare needed for the particular procedure. Examples of such trays aredisclosed in my U.S. Pat. Nos. 5,424,048 and 5,681,539.

FIG. 1 depicts a typical medical tray shown generally at 10. The trayhas a bottom wall 10 a and side walls 10 b extending up from the bottomwall to define a generally rectangular interior space 12. The tray isusually made of a material able to with stand sterilization, e.g.polyphenylsulphone or a non-corroding metal such as aluminum, stainlesssteel or titanium. The bottom wall 10 a of tray 10 is usually formedwith a multiplicity of vent holes 16 arranged in columns and rows toallow for circulation of steam or other sterilizing fluid throughout theinterior space 12. As will be described in more detail presently, theseholes may also function as anchoring points for the retainers andaccessories used to locate various medical instruments within tray 10.

Tray 10 is adapted to contain a plurality of variously shaped medicalinstruments I. In order to retain these instruments in the tray,assorted retainers or accessories may be employed. These may includeknown solitary post assemblies 18 as well as conventional elongatedretainer assemblies 20 and 20′ having notches or slots for receivinginstruments I as shown.

As depicted in FIGS. 1 and 2A, the retainer assembly 20 comprises aunitary retainer 22 molded of a rigid plastic material able to withstandsterilization. The retainer is in the form of an upstanding bladecontaining notches or slots 22 a and having a bottom flange 24 so thatthe retainer has the general shape of an inverted letter T. Threadedholes 26 extend up from the bottom of retainer 22. These holes arespaced apart along the retainer a distance that is an integral multipleof the spacing between the holes 16 in a given row of holes in traybottom wall 10 a. Thus, retainer 22 may be positioned on the tray wall10 a with its holes 26 in alignment with the vent holes 16 in the trayso that the other components of the assembly 20, namely threadedfasteners 28, may be inserted through the vent holes and turned downinto the registering holes 26 in retainer 22 as shown in FIG. 2A.

Instead of being a unitary part as depicted in FIG. 2A, someconventional retainers are composed of two separate pieces which arekeyed together. A retainer such as this is shown generally at 22′ inFIGS. 1 and 2B. That retainer comprises a rigid rail 32 molded of asuitable hard plastic material able to withstand sterilization.Spaced-apart threaded holes 34 extend up from the bottom of rail 32 forreceiving threaded fasteners 28 to secure the rail to the tray bottomwall 10 a in the same manner as retainer 22 described above.

Rail 32 is adapted to receive and support a blade-like instrument holder38 made of a flexible, resilient, sterilizable material such assilicone. The holder 38 may be formed with slits or cut-outs 38 a forholding medical instruments I. In order to mechanically secure theholder 38 to rail 32, the bottom of the holder is flanged to form a key40 which is shaped and sized to slidably engage in a keyway 42 formed inthe upper portion of rail 32.

The posts of assemblies 18 depicted in FIG. 1 may be anchored in asimilar fashion to the tray bottom wall 10 a using threaded fasteners28.

Although these prior retainer assemblies perform their instrumentretaining function satisfactorily, they may not pass new safetyrequirements being proposed by the FDA to ensure that medical trays andtheir contents are free from contamination. That is, more emphasis isbeing placed on being able to demonstrate the ability to thoroughlyclean and sterilize such products. The FDA is particularly concernedwith cleaning and sterilization at mating surfaces such as theundersurfaces of the retainer 22 and rail 32 where they meet the traywall 10 a, as well as the opposing surfaces at the boundary between thesilicone holder 38 and the rail 32 of the retainer assembly 20′ shown inFIG. 2B. If that holder 38 is flexed laterally, an appreciable may openbetween the holder and the rail. All of these locations have thepossibility of trapping bacterial contamination and protecting sameduring the sterilization process. In fact, the only way to ensure aproper cleaning of these surfaces is to dissemble all of the retainerassemblies and remove them from the tray 10 so that all of the parts canbe sterilized separately. Of course, all of the retainer parts must thenbe reassembled in the tray for the next operation. Needless to say, thisis a tedious task and is not desirable from the standpoint ofefficiency. Also, in their disassembled state, the various small partsmay be misplaced or lost while being processed.

SUMMARY OF THE INVENTION

Accordingly the present invention aims to provide a retainer assemblyfor use in a medical tray or other container which minimizes thepotential for bacterial contamination within the tray.

Another object of the invention is to provide a retainer assembly suchas this which does not have to be separated from the tray in order tothoroughly clean and sterilize the tray and assembly components.

Yet another object of the invention is to provide a retainer assemblywhose construction minimizes the likelihood of bacterial contaminationin and around the assembly.

A further object is to provide a retainer consisting of a unitary partwhich may be rigidly anchored to a container wall while resilientlyretaining various medical instruments placed in the container.

Still another object of the invention is to provide such a retainerwhich can be made in quantity relatively inexpensively usingconventional molding or machining techniques.

Another object of the invention is to provide a method of making such aretainer having one or more of the above advantages.

Other objects of the invention will, in part, be obvious and will, inpart, appear hereinafter.

The invention accordingly comprises the several steps and the relationof one or more of such steps with respect to each of the others, and thearticle possessing the features, properties and the relation ofelements, all as exemplified in the following detailed description, andthe scope of the invention will be indicated in the claims.

In general, the present retainer assembly comprises an instrumentretainer for placement in a container such as a medical tray, andfastening means for anchoring the retainer to a wall of that containerat one or more anchoring points.

The retainer has at least one rigid exposed support portion each havingat least one anchoring point for receiving a fastener and a flexible,resilient instrument holding portion bonded to each support portion sothat the retainer is essentially a unitary part completely devoid ofcracks and joints in which bacteria could develop and multiply. Thus,the retainer assembly provides both a secure mechanical attachment tothe container and a holding portion which may be configured toresiliently engage and fix within the container a variety of differentlyshaped and sized medical instruments and devices.

As we shall see, when forming the retainer an intimate bond is obtainedbetween the resilient holding portion and the rigid support portion ofthe retainer by positioning an already formed support portion in a moldand injection molding a holding portion directly onto and around thesupport portion so that the two portions become as one. After themolding process, the holding portion may be cleaned and profiled tosupport various medical instruments and devices.

As will be described in more detail later, the holding portion of theretainer may be in the form of an elongated slotted blade designed toengage around or receive the medical instruments or it may be in theform of a fence or post positioned to corral instruments placed in thecontainer. In each case, the holding and support portions of theretainer are intimately bonded together to minimize any possibility ofbacterial in-growth thereon.

In a preferred embodiment of the invention, the retainer has an integralseal at each anchoring point thereof which, when the retainer isanchored to the container wall, surrounds the fastener at thecorresponding anchoring point thus preventing in-growth of bacteriabetween the retainer and the container wall at that anchoring point. Ifa particular retainer has more than one anchoring point, the retainer ispreferably shaped SO that its anchoring points extend below theremainder of the retainer so that when the retainer is anchored to thecontainer wall by the fasteners, each seal seats against the containerwall. In one preferred embodiment of the invention, the seal is a knifeedge depending from the support portion and encircling the fastener toprovide a high pressure line contact between the support portion of theretainer and the container wall. In a second preferred embodiment of theinvention, the seal is an extension of the holder portion of theretainer which extension forms a flexible resilient line contact sealaround the fastener. Both seals prevent the infiltration of bacteria atthe interface between the retainer and the container wall.

It is a further feature of the invention that the present retainers canbe made relatively inexpensively in quantity using standard molding ormachining techniques. Therefore they should be comparable in cost toconventional retaining devices which do not have the same advantages interms of ease of use and freedom from bacterial build up.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention,reference should be made to the following detailed description taken inconnection with the accompanying drawings, in which:

FIG. 1, already described, is a perspective view with parts broken awayshowing conventional retainer assemblies installed in a medical tray;

FIGS. 2A and 2B are elevational views of the known retainer assembliesshown in FIG. 1;

FIG. 3 is a schematic diagram showing the steps for making the retainercomponent of a retainer according to the present invention;

FIG. 4A is a fragmentary elevational view on a larger scale and withparts in section showing a retainer made in accordance with FIG. 3 andassembled to a container;

FIG. 4B is a fragmentary perspective view of the retainer in the FIG. 4Aassembly;

FIG. 5 is a similar view showing another retainer embodiment;

FIG. 6 is a perspective view illustrating still another retainerembodiment, and

FIG. 7 is a perspective view on a smaller scale illustrating yet anotherembodiment of the invention.

DETAILED DESCRIPTION OF PERFERRED EMBODIMENTS

Referring to FIGS. 4A and 4B and the right hand side of FIG. 3, myimproved retainer shown generally at 48 comprises a rigid supportportion 50 in the form of an elongated beam and an upstanding flexibleresilient blade-like instrument holding portion indicated at 52 which isintimately bonded to support portion 50. The support portion includesone or more legs 50 a each of which extends below portion 50 per se toprovide an anchoring point. As best seen in FIGS. 4A and 4B, each leg 50a is formed with a threaded passage 54 which extends in from the lowerend of the leg for anchoring the retainer to the wall of a containersuch as the bottom wall 10 a of the medical tray illustrated in FIG. 1.For this, each leg 50 a is located on base portion 50 so that it can beplaced in register with a hole 16 in tray wall 10 a. This enables afastener 28 to be inserted from below the tray through that registeringhole and screwed into the passage 54 in the corresponding leg 50 a. Ofcourse, if the retainer legs 50 a do not line up with the holes 16 inthe tray wall, additional such holes may be drilled through that wall atthe appropriate places to accommodate the retainer. In any event, whenthe retainer is anchored to the tray wall 10 a by fasteners 28, theretainer assembly is complete.

Although superficially the present retainer 48 appears similar to someprior instrument retaining brackets of this general type such as the onedepicted in FIG. 2B, it differs in several important respects. Moreparticularly, the support portion 50 of the present retainer 48 isactually used to help form the holding portion 52 thereof.

More particularly, as shown in FIG. 3, in a first step, the rigidsupport portion 50 is formed of a suitable sterilizable plastic or metalusing a conventional molding or machining process. It is made not onlywith one or more legs 50 a, but also with an integral upstanding rail 50b with which the holding portion 52 will interfit. Since the illustratedsupport portion 50 is in the form of an elongated beam, the rail incross section resembles the letter T. Of course, the rail 50 b may beotherwise shaped to interfit with holding portion 52 as will bedescribed. For example, portion 52 may comprise a column of spaced-apartupstanding posts or barbs.

In any event, after the support portion 50 is formed, in a second step,that portion is placed in a mold 60 having a cavity 60 a shaped toaccommodate support portion 50 so that that portion constitutes one wallof the cavity and so that the rail 50 b of portion 50 projects into thecavity. The mold 60 may be of any standard design having an injectionport 60 b for injecting a plastic material P into cavity 60 a thatcavity being shaped to form the instrument holding portion 52 of theretainer. Preferably, the mold includes a vent passage 60 c to vent airfrom cavity 60 a as the cavity is being filled with plastic material.

The plastic material P may be any material conventionally used toresiliently hold medical instruments and devices, the preferred materialbeing silicone.

During the injection molding process, the plastic material P isdeposited directly onto and around the bonding surfaces of the supportportion 50 exposed in mold cavity 60 a. Thus an intimate bond is formedbetween the plastic P and those surfaces. Resultantly, when the moldingprocess is completed and the support portion is removed from mold 60,the plastic material P that has formed the holding portion 52 of theretainer is not only mechanically anchored to the rail 50 b of supportportion 50, but also it is intimately bonded to the bonding surfaces ofthat portion so that the retainer is completely devoid of any gaps,cracks or crevices that could provide refuge for bacteria and othercontaminants.

After the injection molding step has been completed, the molded productmay be cleaned and its holding portion 52 profiled, in a third step, toform the desired instrument retaining slots and notches 56 using aconventional water jet or die-cutting process.

The present retainer differs from others also in that its leg(s) 50 aextend well below support portion 50 and holding portion 52. Also, theleg(s) in cross section are larger than the holes 16 in tray wall 10 a.Resultantly, when the retainer is anchored to the tray wall 10 a asshown in FIG. 4A, the leg(s) act as spacers so that a relatively largegap G exists between the retainer per se and the tray wall. In otherwords, the retainer only contacts the tray wall directly underneath theleg(s) 50 a so that when the tray and its contents are being sterilized,the sterilizing fluid can circulate underneath the retainer per se sothat there can be no bacterial build up there.

As for the small areas underneath the retainer legs 50 a, it has beenfound that these areas do not tend to trap contamination because eachleg 50 a is held against the tray wall 10 a under relatively highcontact pressure due to the associated fastener 28. However, in apreferred embodiment of the invention, an especially high contactpressure engagement of each leg 50 a with the tray wall 10 a is assuredby forming each leg end with a depending circular knife edge 50 b at theperimeter of leg 50 a and which surrounds the fastener hole 54 as shownin FIGS. 4A and 4B. Thus when the associated fastener 28 is turned downinto hole 54, the knife edge 50 b is urged against the tray wall 10 aunder very high pressure due to its small contact area so that there isno possibility of biological contaminants passing between the leg andthe container wall.

Refer now to FIG. 5 which shows another retainer embodiment indicated at70 in which a support portion 72 of the retainer is fully encapsulatedwithin a holding portion 74 except for the undersurface of each leg 72 aof the support portion. In other words, the holding portion 74 isinjection molded around support portion 72 so that a wall 74 a of theholding portion extends under the support portion and around the side ofeach leg 72 a. Preferably also, that wall extends beyond the end of eachleg to form a flexible resilient lip or flange 74 b as shown in FIG. 5.Thus, when the retainer is positioned in the tray 10 and anchored to thetray wall 10 a by fasteners 28 as in FIG. 1, each flexible resilient lip74 b is drawn against the tray wall forming a resilient knife edge sealaround the associated fastener which prevents the introduction ofcontaminants at each anchoring point of the retainer to the tray wall.

FIG. 6 illustrates yet another retainer embodiment shown generally at80. In this case, the flexible, resilient instrument holding portion 82comprises a pair of sleeves 82 a injection molded around a pair ofspaced-apart rigid posts 84 with a web 82 b extending between the twosleeves. The posts 84 comprise the support portion of this retainer.Preferably, the posts have ends 84 a which extend beyond or below thelower ends of sleeves 82 a and threaded fastener holes 86 extend in fromthose post ends. Thus, when retainer 80 is secured to tray wall 10 a byfasteners 28 in the manner of retainer 48 described above, the holdingportion 82 thereof is spaced above the tray wall. Also of course, theprojecting ends 84 a of posts 84 may be formed with a sealing flangesimilar to flange 50 b on retainer 48 described above and shown in FIGS.4A and 4B. Alternatively, the sleeves 82 a may extend down around thepost ends 84 a to form a resilient seal similar to seal 74 b describedabove in connection with retainer 70 in FIG. 5. In any event, whenretainer 80 is secured to the tray wall 10 a, it constitutes a fence orbarrier which may be used to restrain or corral a medical instrument ordevice within the tray 10.

Of course, other fasteners may be used in my retainer assembly to anchorthe various retainer embodiments to the container wall. For example, theretainers may be permanently anchored to the tray by rivets. Also, toaccommodate trays having different wall thicknesses, the assembly mayinclude the fastening means of the type disclosed in my application Ser.No. 11/177,541, filed Jul. 8, 2005, the contents of which are herebyincorporated by reference herein.

FIG. 7 shows generally at 90 another retainer embodiment having a rigidsupport portion 92 onto which is injection molded a flexible resilientinstrument holding portion 94. Support portion 92 may be a stamped metalpart formed with one or more legs 92 a which extend from an edge ofholding portion 94. These legs may be used to anchor the retainer tocontainer wall 10 a by inserting fasteners 96 e.g. screws, rivets orfriction pins, through the legs and the wall. As with the other retainerembodiments, the holding portion 94 forms an intimate bond with thesupport portion 92 so that the retainer is devoid of potentialcontamination sites.

Thus the present retainer assemblies provide a rigid connection to thecontainer wall and a resilient engagement with the medical instrumentswhich they retain. Yet they are devoid of joints and interfaces whichcould be sites for bacterial infestation. Retainer assemblies made inaccordance with this invention can remain in place in a medical tray orother container during sterilization with assurance that after thesterilization process is completed, the tray and its contents will beclean and free of bacterial contamination and will conform to anystandards imposed by FDA. This ability to leave the retainer(s) in thetray will make the sterilization process much more efficient and willfree up medical personnel to do other important tasks.

It will thus be seen that the objects set forth above, amoung those madeapparent from the preceding description, are efficiently attained. Also,certain changes may be made in carrying out the above method and in theconstructions set forth without departing from the scope of theinvention. For example, retainers in the form of silicone sheathed postssimilar to posts 18 in FIG. 1 may be made according to this inventionsimply eliminating the web 82 b when molding the sleeves 82 a of theFIG. 6 retainer. Therefore, it is intended that all matter contained inthe above description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the inventiondescribed herein.

1. A retainer assembly for retaining a medical device in a container having a wall with perforations, said retainer assembly comprising a retainer including a rigid support portion having at least one leg, a flexible, resilient instrument holding portion intimately bonded to the support portion so that the retainer is devoid of cracks and crevices between said portions, each said leg extending from the holding portion to a free end, and an axial passage extending into each leg from said free end thereof so that the retainer may be positioned on said wall with each axial passage in register with a perforation in said wall, wherein said wall is contacted by said leg only at a surface directly underneath said leg, and a fastener extending into the passage of each leg and the underlying perforation from below said wall to anchor each leg to said wall under pressure; and, a seal between each leg and the wall.
 2. The assembly defined in claim 1 wherein each leg is formed with a peripheral knife edge at the free end thereof.
 3. The assembly defined in claim 1 wherein said holding portion includes a wall extension surrounding each leg of the support portion.
 4. The assembly defined in claim 3 wherein the wall extension surrounding each leg protrudes beyond the free end of that leg to form a flexible resilient sealing lip at the periphery of said free end.
 5. The assembly defined in claim 1 wherein the passage in each leg is threaded, and each fastener is a threaded fastener.
 6. The assembly defined in claim 1 wherein each fastener is a rivet or friction pin.
 7. The assembly defined in claim 1 wherein the support portion comprises an elongated beam having locking surfaces, and said holding portion comprises an elongated blade which is coextensive with the beam and which mechanically interfits with said surfaces.
 8. The assembly defined in claim 1 wherein the support portion comprises a rigid post, and the holding portion comprises a sleeve surrounding the post except at an end portion thereof which constitutes said at least one leg.
 9. The assembly defined in claim 8 wherein the support portion also includes an additional rigid post spaced parallel to said post; an additional sleeve surrounding the additional post except at an end portion thereof which constitutes a second leg, and a web extending between said sleeve and said additional sleeve.
 10. The assembly defined in claim 1 and further including at least one cut-out in said holding portion for receiving a medical device.
 11. The assembly defined in claim 1 wherein the support portion is of a plastic material or metal.
 12. The assembly defined in claim 11 wherein the holding portion is of a silicone material.
 13. The assembly of claim 1, further comprising a sealing flange formed between the leg and the wall thereby providing the seal.
 14. The assembly of claim 1, wherein each leg is mounted about only one perforation.
 15. The assembly of claim 1, further comprising a fluid path between the wall and the retainer.
 16. The assembly of claim 1, wherein the at least one leg further comprises at least two legs and, wherein the assembly further comprises an air gap formed between the legs, above the wall, and beneath the retainer.
 17. The assembly of claim 1, wherein the at least one leg further comprises a plurality of legs and each of the legs is mounted about only one perforation. 